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backup windows large datasets

Backup Windows and the Challenge of Large Datasets

by Laura Knight

You’ll hear the term “backup window” come up a lot when talking about how much data a solution can back up. Put plainly, this means the amount of time assigned for backups to occur. If you schedule backups to run between 8pm and 8am, for instance, then you have a backup window of 12 hours.

In a perfect world, backups would always be completed in their allotted window and we could all just move on with our day. Unfortunately, that’s often not the case. As dataset sizes increase, the amount of data that needs to be transferred in nightly backups can be more than the backup solution can handle.

For example, if you need to transfer 200GB between 8pm and 8am, but your backup solution can’t finish backing up all of that data in those 12 hours, you run into some trouble. You’re left with two choices: extend your backup window or back up less data.

When the Backup Window Just Isn’t Enough…

If you extend your backup window, employees may not be too happy – you risk interrupting their work with serious server performance issues. If you have to extend your backup window beyond 24 hours, you run into a different problem: you can no longer accomplish daily backups (since by definition, if it takes more than 24 hours, you can’t do it every day). This puts your data at greater risk in case of a disaster, as you have fewer backups to fall back on.

The other choice would be to back up less data – which is also not ideal. The most obvious drawback is whatever data doesn’t make the cut is at increased risk of being lost in a disaster. You’re then stuck making difficult decisions about which data is important enough to back up daily and which isn’t, adding another layer of administrative headache. You also open up the possibility of misclassifying something, and then losing it in a disaster.

So if your backups aren’t fitting into their window, and neither extending your backup window nor reducing your dataset are good options, what can you do? Well, it’s time to look at the third element: the backup solution.

…The Backup Solution Needs to Up Its Game

While all backup solutions serve the same fundamental purpose – making sure you have extra copies of your data kept safe from disaster – how they go about it can be very different. A solution’s architecture makes a big impact. This is especially true in the cloud, where WAN optimization can make the difference between a backup that finishes in hours and a backup that finishes in days (related: we just implemented new enhancements to allow large files take full advantage our WAN optimized architecture, and the speed test results were pretty dramatic).

A faster backup solution lets you have the best of both worlds – nightly protection for your entire dataset, and a reasonable backup window. Since datasets are only going to get bigger, having a solution that can back that data up daily and on time becomes essential.

Laura Knight
Laura Knight

As Content Marketing Manager, Laura writes, edits, designs and is always on the lookout for new ways to tell the Zetta story.